lot of people are concerned that the use of classic D&D magic in D&D Next—where casters prepare spells each day, consume them as they cast them, and regain spells after they rest—encourages groups to get into one fight then camp. This phenomenon is sometimes referred to as the five-minute workday, where adventurers spend about five minutes in a dungeon before leaving to rest.
We do not want groups to feel that they must rest after a single battle. If you're exploring a dungeon, we want to make sure that you feel like you can make good progress each day. We're also aware that classes that need to rest to regain spells are the main source of this pressure, though hit point loss also plays a role. Since the game balances the fighter's and rogue's staying power against the wizard's and cleric's spell attrition, it's important that the "workday" last long enough for the rogue and fighter to shine.
As we did in 4th Edition, with D&D Next we are paying close attention to the basic math of the game and how monsters, characters, spells, and healing interact. Rather than focus on the encounter, we are now focusing on the adventuring day. That means that during the typical adventure, we expect the average party to defeat X levels worth of monsters over Y rounds of combat. In other words, we're assuming that an adventure includes a certain amount of combat, and this amount is defined in terms of rounds and enemies.
Obviously, the math addresses only one of the three pillars: combat. We're using hit points as our tracking mechanism here. Since the other two pillars, interaction and exploration, don't normally cause you to lose hit points, we can make a direct comparison between spells and nonmagical abilities to make sure each class can contribute in combat. For instance, a rogue's ability to be stealthy needs to be matched up against the invisibility spell. Spells can give you an edge, but so can the right background or class ability. On top of that, a character can always make an ability check to attempt something. You're never stuck without options.
We can rate things such as traps along the same lines as monsters. Experience awards for interaction and exploration are more in the realm of the Dungeon Master's hands than a strict, mechanical definition, but both will appear in the final experience point system with full guidelines.
What does this mean for the five-minute adventuring day? DMs will have a crystal clear guideline on how many rounds of combat a group should tackle before resting. If the group spends less time in fights, casters grow stronger. If the characters spend more rounds fighting, the fighter and rogue grow stronger. The solution to the problem rests in the DM's hands, who can use the tools and guidelines that we provide, plus keep track of how long fights take and adjust adventures accordingly.
As an example of the differences between casters and other characters, a wizard is far more powerful in comparison to a fighter if every monster you expect to fight during an adventure charges the group at once. A fireball damages almost every critter, and web catches them all in its grasp. Meanwhile, the fighter and rogue work through a few enemies at a time. When you compress fights, a wizard's and cleric's combat spells become much more powerful.
In comparison, imagine if the party fought one monster at a time. The wizard might never opt to cast a spell, since something such as fireball is less effective overall if it blasts only one critter. The fighter, on the other hand, can cut a swathe through the party's enemies, hacking them down one at a time.
The important thing from an R&D perspective is that both extremes, and all the points in between, are options for DMs. If that's how you want to run D&D, that's your call. Our job as designers is not to tell you how to play, but to give you the ability to run a game that matches what you want out of D&D. If the five-minute workday bothers you, you have the tools to judge its effect on your game and can take steps to fix it. If you don't care or have never noticed the issue, we don't make it one for you.
Mike Mearls is the senior manager for the D&D research and design team. He led the design for 5th Edition D&D. His other credits include the Castle Ravenloft board game, Monster Manual 3 for 4th Edition, and Player’s Handbook 2 for 3rd Edition.